Various ring balance changes:
* Remove =susChr (first commented out in 2010)
* Replace rings of rFire & rCold with one ring, rFire&Cold
* Remove never-implemented =Dark
* Move =Flames/Ice/Lightning/Acid higher in the dungeon
* No rings are now native <DL10
Make TELEPORT flag trigger teleport 2x as often.
Tweak mushrooms: fast recovery heals some HP, clear mind heals 10SP.
Substantially increase duration of telepathy from ,SecondSight and rConf from ,ClearMind.
Double speed of Terror effect.
Make all DSM's breath weapons do at least 150 damage
Merge remote-tracking branch 'takkaria/balance'